- Change the code to do rcu_read_lock() instead of taking tasklist_lock,
it is safe to get_task_struct(p) if p was found under RCU.
However, now we must not use process's sighand/signal, they may be NULL.
We can use current->sighand/signal instead, this "process" must belong
to the current's thread-group.
- Factor out the common code for 2 "if (timer_event_spec)" branches, the
!timer_event_spec case can use current too.
- use spin_lock_irq() instead of _irqsave(), kill "flags".
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: mingo@elte.hu
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
36b2f04600